eric ollivier 07/06/05
DESCRIPTION
New gas exchange system to provide high amount of EGR in DI diesel engines – A preliminary literature survey. Eric Ollivier 07/06/05. Intensified EGR cooling. CICERO EGR project. NOx fuel consumption trade-offs. US 07 NOx-Scenarios. Injection (pressure, Multi-hole nozzle, strategy …). - PowerPoint PPT PresentationTRANSCRIPT
![Page 1: Eric Ollivier 07/06/05](https://reader035.vdocuments.fr/reader035/viewer/2022081508/56814641550346895db34b24/html5/thumbnails/1.jpg)
1
New gas exchange system to provide high amount of EGR in DI diesel engines – A preliminary literature
survey.
Eric Ollivier
07/06/05
![Page 2: Eric Ollivier 07/06/05](https://reader035.vdocuments.fr/reader035/viewer/2022081508/56814641550346895db34b24/html5/thumbnails/2.jpg)
2
NOx fuel consumption trade-offs
Injection (pressure,Multi-hole nozzle, strategy …)
Intensified EGR cooling
US 07 NOx-Scenarios
CICERO EGR project
Correlation between emissions reduction and fuel consumption in passenger car DI diesel engines (study supported by FFV workgroup) [Lamping et al., MTZ, 07/01 ].
Intensified EGR cooling
![Page 3: Eric Ollivier 07/06/05](https://reader035.vdocuments.fr/reader035/viewer/2022081508/56814641550346895db34b24/html5/thumbnails/3.jpg)
3
Required increase of boost pressure to implement 10% EGR at a constant speed [Arnold, 2004].
![Page 4: Eric Ollivier 07/06/05](https://reader035.vdocuments.fr/reader035/viewer/2022081508/56814641550346895db34b24/html5/thumbnails/4.jpg)
4
• Positive pressure differential between turbine outlet and compressor inlet
• DPF
•Two stages of cooling : less EGR needed
• Condensation : liquid water and lubricating oil, and acid solution in the intake area
• Big intake volume : homogeneous mixture but high response time
The Low Pressure EGR circuit :
![Page 5: Eric Ollivier 07/06/05](https://reader035.vdocuments.fr/reader035/viewer/2022081508/56814641550346895db34b24/html5/thumbnails/5.jpg)
5
• Negative pressure differential between turbine outlet and compressor outlet • Fouling of the EGR cooler • Coordination of EGR valve/VGT vanes
The High Pressure EGR circuit :
![Page 6: Eric Ollivier 07/06/05](https://reader035.vdocuments.fr/reader035/viewer/2022081508/56814641550346895db34b24/html5/thumbnails/6.jpg)
6
Thermodynamic comparison of the LP and HP EGR loops :
Reduced Mass Flow as a function of the compressor pressure ratio, in HP and LP EGR loop to provide 30% EGR at 2500 rpm and
12 bar BMEP [Weber et al., 2005]
Passenger car, specific output power of 50kwk/l
![Page 7: Eric Ollivier 07/06/05](https://reader035.vdocuments.fr/reader035/viewer/2022081508/56814641550346895db34b24/html5/thumbnails/7.jpg)
7
Lambda maps :
![Page 8: Eric Ollivier 07/06/05](https://reader035.vdocuments.fr/reader035/viewer/2022081508/56814641550346895db34b24/html5/thumbnails/8.jpg)
8
PMEP maps :
![Page 9: Eric Ollivier 07/06/05](https://reader035.vdocuments.fr/reader035/viewer/2022081508/56814641550346895db34b24/html5/thumbnails/9.jpg)
9
BSFC maps :
![Page 10: Eric Ollivier 07/06/05](https://reader035.vdocuments.fr/reader035/viewer/2022081508/56814641550346895db34b24/html5/thumbnails/10.jpg)
10
Operating points on the compressor map for 100% load and 1.7λ for HPL and LPL of a Euro III – Euro IV engine (Langridge and Flesser, 2002)
Commercial Vehicle engine, 400kW @ 1900 rpm
![Page 11: Eric Ollivier 07/06/05](https://reader035.vdocuments.fr/reader035/viewer/2022081508/56814641550346895db34b24/html5/thumbnails/11.jpg)
11
HPL EGR LPL EGR
100% load, 1.7 Air Excess, 80% rated speed 100% load, 1.7 Air Excess, 80% rated speed
BSFC/NOx trade-off for 100% load, 80% rated speed and 1.7 air excess ratio for HPL and LPL (Langridge and Flesser, 2002)
Commercial Vehicle engine, 400kW @ 1900 rpm
![Page 12: Eric Ollivier 07/06/05](https://reader035.vdocuments.fr/reader035/viewer/2022081508/56814641550346895db34b24/html5/thumbnails/12.jpg)
12
Virtual turbocharging system enabling to reach sufficient amount of EGR to fulfill Euro 5 (Langridge and Flesser, 2002)
Compressor Efficiency : 77% Turbine Efficiency : 75%
Required amount of EGR : 20%
Commercial Vehicle engine, 400kW @ 1900 rpm
![Page 13: Eric Ollivier 07/06/05](https://reader035.vdocuments.fr/reader035/viewer/2022081508/56814641550346895db34b24/html5/thumbnails/13.jpg)
13
(VGT as an alternative to the wastegate)
bypass
Low pressure stage turbocharger
Regulated Two-stage Turbocharging System, R2S (on 4 cyl. 4,6L engines, other?)
Air charge cooler
bypass
High pressure stage turbocharger
Two stage turbocharging systems (Buchwald et al., 2006)
Alternative, promising , future turbocharging systems to implement high amount of EGR:
![Page 14: Eric Ollivier 07/06/05](https://reader035.vdocuments.fr/reader035/viewer/2022081508/56814641550346895db34b24/html5/thumbnails/14.jpg)
14
Two stage turbocharging compressor map enabling to reach sufficient amount of EGR to fulfill Euro 5 (Langridge and
Flesser, 2002)
Commercial Vehicle engine, 400kW @ 1900 rpm
![Page 15: Eric Ollivier 07/06/05](https://reader035.vdocuments.fr/reader035/viewer/2022081508/56814641550346895db34b24/html5/thumbnails/15.jpg)
15
Full load characteristics of the engine
Aim : combustion lambda λc= 2Inlet charge temperature = 40ºCEGR-rate = 60%
Two stage turbocharging systems (Buchwald et al., 2006)
![Page 16: Eric Ollivier 07/06/05](https://reader035.vdocuments.fr/reader035/viewer/2022081508/56814641550346895db34b24/html5/thumbnails/16.jpg)
16
2 radial compressor wheels in series
The Low speed turbo by Garett Engine boosting System (S. Arnold, 2004)
![Page 17: Eric Ollivier 07/06/05](https://reader035.vdocuments.fr/reader035/viewer/2022081508/56814641550346895db34b24/html5/thumbnails/17.jpg)
17
Performance of the LST compressor stage against the state of the art single stage compressor
(Arnold, 2004)
![Page 18: Eric Ollivier 07/06/05](https://reader035.vdocuments.fr/reader035/viewer/2022081508/56814641550346895db34b24/html5/thumbnails/18.jpg)
18
Intermediate EGR route, (Arnold 2004)
![Page 19: Eric Ollivier 07/06/05](https://reader035.vdocuments.fr/reader035/viewer/2022081508/56814641550346895db34b24/html5/thumbnails/19.jpg)
19
Testing & calculation database
Experience,know how Bibliographic
Research
Ideas
Think-Tank
N Configurations
Numerical Calculations
Selection of the more promising configurations
SimulationsFor refining?
1 D Simulation for new EGR circuit configurations
Test bench?
….
![Page 20: Eric Ollivier 07/06/05](https://reader035.vdocuments.fr/reader035/viewer/2022081508/56814641550346895db34b24/html5/thumbnails/20.jpg)
20
Full load compressor map
Aim : combustion lambda λc= 2Inlet charge temperature = 40ºCEGR-rate = 60%
Two stage turbocharging systems (Buchwald et al., 2006)